Unfortunately, 10 days ago, our employee has inadvertently changed an account's quota from 4gb to 5mb. As you guess. As you might guess, there are several emails has returned back as "Quota exceeded". However, I see these emails under System > Mail Logs > Received Mails.

But, there is no any file under "cur" directory.

Are these mails located in the server? If yes, please help me about location or any information.